I am about to put my 88 spider away for the winter months. (November till May). I live in the Michigan Area so the winters are harsh. I would prefer to put the car away and not touch it so I consulted with my mechanic who advised me to do the following. Gas stabalizer, oil change, wheels off ground, and cardboard under car to prevent moisture. (said not to use plastic on concrete). He also said to trickle charge the battery. Is this enough or should I do more. He is a knowledgable guy who worked as a mechanic back in Italy for Alfa so I tend to listen to him. Any advise would be great.